VALIDITY OF THE WATER-ABSORPTION TEST FOR CHARACTERIZING COVER CONCRETE

The authors justify their choice concerning the water absorption test for assessing both cover concrete porosity and largest capillary size, which are significant factors for concrete durability. In this way they extend to concrete an existing model used for terra cotta. The criterion used is the amount of water absorbed after one hour. This value is sufficiently representative of the mean radius of the largest capillaries. The results show that the absorption test can assess the effects of cement content on cover concrete porosity. Relating to these same results, the absorption test makes it possible also to take into account the beneficial effects of curing on capillary size. Correlations between carbonation depth and amount of water absorbed after one hour confirm the validity of these tests to assess the resistance of concrete to carbonation.